Publican is a tool for publishing material authored in DocBook XML. This guide explains how to to create and build books and articles using publican. It is not a DocBook XML tutorial and concentrates solely on using the publican tools. See docbook.org for information about DocBook XML.

Publican began life as an internal tool used by Red Hat's Documentation Group (now known as Engineering Content Services). On occasion, this legacy is visible.

The Branding functionality allows you to create your own presentation rules and look, over-riding many parts of the default style to meet your publishing needs. Choices executed in code, however, are not changeable.

Entities, for example, can be validly defined in any XML file. However, to ensure the DTD declaration is present, valid and standardized, Publican rewrites the declaration in every XML file before it builds a book or article. Consequently, all entities declared in all XML files are lost. Publican, therefore, requires you define Entities in the Book_Name.ent file (see Section 3.3.7, “Book_Name.ent”).

As publishing workflows grow, unrestrained Entity definition leads to Entity duplication and other practices that cause maintenance difficulties. Consolidating Entity definitions in a single, predictable place alleviates these maintenance issues and helps the automation of the build process stay robust.

Entities also present an essentially insurmountable obstacle to quality translation (see Section 3.3.7, “Book_Name.ent”). Consequently, while we are not reducing the Book_Name.ent file's functionality, we are no longer considering requests to add functionality or features associated with Entity use.